Topic       : TOS - The Operating System
Author      : 
Version     : tos.hyp (December 19, 2008)
Subject     : Programmieren/Atari
Nodes       : 3010
Index Size  : 93790
HCP-Version : 5
Compiled on : Atari
@charset    : atarist
@lang       : 
@default    : Title
@help       : 
@options    : +g -i -s +x +zz -t4
@width      : 70
View Ref-File8.11.6  form_error                                                 TOS

 Name:         »Form error« - Display an alert box form for TOS 
               errors.

 Opcode:       53

 Syntax:       int16_t form_error ( int16_t fo_enum );

 Description:  The call form_error outputs an MS-DOS error number as a 
               plain text description (i.e. in an alert box form that 
               contains a stop sign icon at the left side of the box, 
               a text string holding an explanatory error message or 
               just 'TOS error #X' and a 'Cancel' button).

               The parameter fo_enum is here the corresponding error 
               number.

               Note: This function is present for reasons of compa- 
               tibility to PC-GEM. Hence on TOS systems one first has 
               to translate the GEMDOS error number to the MS-DOS 
               coding. For the conversion (GEMDOS -> MS-DOS) one can 
               use, say, the following formula: ( fo_enum) - 30.

               In N.AES there is an extended form of form_error with 
               all GEMDOS error-codes. Its presence can be checked 
               with appl_getinfo (opcode 64).

               Geneva interpreted a negative number as a GEMDOS/BIOS 
               error-code, and an appropriate error-message is 
               displayed. For instance, the call:
               form_error(-33);
               produces an alert with the text 'There is no file with 
               this name'.

 Return value: This will be the index (1-3) of the selected exit 
               button. However, with current GEM versions only one 
               button is available in error alerts.

 Availability: All AES versions.

 Group:        Form library

 See Also:     Binding   form_xerr   form_err in N.AES